.NET / C#

Dependency Injection (DI) helps us to change the behavior of parts of our program on the fly. This is especially neat when you want to test your domain services against a mocked data-store. But what if you need to change the behavior of your API based on a request header?

Yesterday I had a discussion with my colleague Robert Kranenburg about this. He showed an example of a console application changing its behavior based on an argument. I took the idea and converted it into .NET Core 3.1 code to change behavior based on a cookie.

I love attribute validation! They can be used for a myriad of things. In .NET Core MVC we use them to validate models that come into our controllers. In one of our projects we kept running into the same thing: we need to validate a value against an array of pre-defined values. So we wrote some base validation attributes.

I like to validate my application configuration upon startup. Especially when doing local development, I want to know which application settings are missing. I also like to know where I should add them. This blog shows how to implement validation of your configuration classes using data annotations.

We have a .NET service that needs to connect with Jira to create, update and read issues. It would be easy if we could use a username & password for authentication, but for this integration we need to implement the connection to Jira with a Private Key. All requests have to be signed with OAuth.

We live in a day and age in which we can choose a data-store that matches the characteristics of our apps and (micro) services. Lately we’ve been looking into Redis as a high performing store for last viewed items. In this blog I’ll look show how to create a POC with the redis-cli and then implement it using .NET Core. We’ll be using the sorted set structure.

I love how we can use appsettings.json files to configure applications in the .NET Core platform. The JSON-format feels a lot less bloated than the old XML appSettings config I used to work with. In this blog I’ll explore how to load a dictionary-style settings class as an IOption. This can be very useful when working with dependency injection.

In ASP.NET Core we are used to have multiple appsettings.json files with settings that differ per environment. I want to do the same in a Console Application. This makes debugging the application easier.

I can almost hear you thinking: “What super-weird problem are you trying to solve!?” Well… it is kind of an abstract one! Imagine you have a dictionary of objects and a separate list of keys in a certain order. Now suppose you want an ordered dictionary based on the list of keys.

When you are used to building web applications, you kind of get hooked to the ease of Dependency Injection (DI) and the way settings can be specified in a JSON file and accessed through DI (IOptions). It’s only logical to want the same feature is your Console app.

One of the big advantages of the .Net regular expression implementation is named groups.  Today I want to show how to leverage named regular expression groups to build a routing constraint that will map each group value to a named route value.